Dual-mode hydrocarbon source gas detection device and method based on non-dispersive infrared spectroscopy

Abstract

The invention relates to the technical field of petroleum engineering logging equipment, in particular to a dual-mode hydrocarbon source gas detection device and method based on non-dispersive infrared spectroscopy, and the method comprises the following steps: a gas permeation unit is used for separating hydrocarbon gas, and a non-dispersive infrared light source is used for generating a dual-light-path independent transmission spectrum and outputting gas spectrum data; the arbitration module generates an arbitration decision result with an optical path mode mark; the analysis module is used for analyzing the pulse signal, identifying a spectrogram form and outputting an analysis result containing a concentration value and a stratum permeability classification code; and the output module fuses the concentration value, the light path mode mark and the classification code to generate depth concentration form triple data. Dynamic release characteristics are arbitrated and matched through double optical paths in real time, transient pulse signals are captured through short optical paths, peak width symmetry degree characteristics are recognized by an analysis module and converted into stratum parameters, and time depth dimensions are associated by an output module to form a non-tampering record chain. Stratigraphic signal missed judgment caused by mismatching of a manual detection period and gas release dynamic characteristics is eliminated.

Description

Technical Field

[0001] The present invention relates to the technical field of petroleum engineering logging equipment, and in particular to a dual-mode hydrocarbon source gas detection device and method based on non-dispersive infrared spectroscopy. Background Art

[0002] The dual-mode hydrocarbon gas detection device based on non-dispersive infrared spectroscopy utilizes the principle of infrared radiation transmission. Gas molecules selectively attenuate light intensity in characteristic absorption bands, and the attenuated signal is analyzed to quantify the concentration of hydrocarbons, such as methane. In the presence of hydrocarbon source gas, molecular vibrations absorb specific infrared wavelengths. The detector measures the energy loss of the transmitted light and infers the gas content. The dual-mode structure integrates two operating modes: high response speed and strong anti-interference capabilities. The former optimizes real-time dynamic monitoring requirements, while the latter suppresses the influence of coexisting components through path switching. For example, it balances detection speed and accuracy in complex industrial emissions, thereby improving system adaptability and reliability, and widely serving oil and gas pipeline safety maintenance and chemical process control.

[0003] The fundamental flaw of existing gas logging technology in gas detection lies in the conflict between intermittent manual operations and the dynamic characteristics of formation gas release. For example, in limestone formation exploration, hydrocarbon gases released from porous reservoirs present short, high-concentration pulses. However, existing equipment requires on-site personnel to manually replace adsorption tubes to enrich the gas and restart the calibration program, which takes more than 8 minutes. By the time detection is restored, the critical gas peak has decayed to the background level, causing weak karst pores to be misjudged as invalid layers in the logging curve, ultimately causing the main production layer to be mistakenly drilled through during the oil test operation. Summary of the Invention

[0004] In response to the shortcomings of the existing technology, the present invention provides a dual-mode hydrocarbon source gas detection device and method based on non-dispersive infrared spectroscopy to solve the problem of missed detection of key formation signals due to the mismatch between the dynamic release of hydrocarbon gas and the manual intervention detection cycle.

[0005] In order to solve the above technical problems, the specific invention of the present invention is as follows: In a first aspect, the present invention provides a dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy, comprising: A data acquisition module is used to collect dynamically released hydrocarbon gas through a gas permeation unit, generate dual-path independent transmission spectra using a non-dispersive infrared light source, and output gas spectrum data including a transmittance matrix; an arbitration module, configured to arbitrate the gas spectrum data, dynamically select a short optical path or a long optical path output mode according to a confidence index, and generate an arbitration decision result including an optical path mode label; an analysis module, configured to receive the gas spectrum data and the arbitration decision result, analyze the pulse signal and identify the spectral morphological features, and output the pulse signal analysis result including the concentration value and the formation permeability classification code; an output module, configured to fuse the concentration value in the pulse signal analysis result, the optical path mode mark in the arbitration decision result, and the formation permeability classification code, and output triplet data to the logging system, wherein the triplet data includes depth data, concentration data, and morphology data; The gas spectrum data output by the data acquisition module is transmitted to the arbitration module and the analysis module, the arbitration decision result output by the arbitration module is transmitted to the analysis module and the output module, the pulse signal analysis result output by the analysis module is transmitted to the output module, and the output module pushes triplet data to capture transient gas release characteristics to solve the problem of missed judgment caused by the mismatch between the manual intervention detection cycle and the dynamic release signal.

[0006] Furthermore, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy described in the present invention, the gas permeation unit includes a fluoropolymer semipermeable membrane, which isolates liquid and rock debris while allowing hydrocarbon gas molecules to penetrate into the detection cavity; The permeated hydrocarbon gas molecules are transmitted to the detection cavity, and a non-dispersive infrared light source irradiates the gas molecules in the detection cavity to generate gas spectrum data.

[0007] Furthermore, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy described in the present invention, the dual-path beam splitter receives a non-dispersive infrared light source and splits the incident light into a short optical path channel beam and a long optical path channel beam; The short optical path channel light beam illuminates the first detector through a direct path to generate first spectral data; The long optical path channel light beam folds the light path through the reflector group and then illuminates the second detector to generate second spectral data; The first spectral data and the second spectral data are combined to form the gas spectral data, which is then transmitted to the arbitration module.

[0008] Furthermore, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy of the present invention, the arbitration module calculates the short optical path signal-to-noise ratio as a partial confidence indicator, and the short optical path signal-to-noise ratio quantifies the signal reliability of the characteristic absorption peak in the gas spectral data; At the same time, the long optical path interference suppression rate is calculated as another confidence indicator. The long optical path interference suppression rate evaluates the anti-interference ability of the interference band in the gas spectrum data; The confidence index is input into the arbitration rule execution submodule, which selects the optical path mode according to the confidence index and outputs the arbitration decision result.

[0009] Furthermore, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy of the present invention, the arbitration rule execution submodule receives the confidence index and selects the short optical path output mode according to whether the characteristic absorption peak change rate in the confidence index exceeds a set threshold; When the environmental interference parameter exceeds the standard, the long optical path output mode is forced to be selected, and the component corresponding to the long optical path interference suppression rate of the environmental interference parameter exceeds the standard; The submodule outputs the arbitration decision result to the analysis module and the output module, and the light path selection mark is generated from the decision result.

[0010] Furthermore, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy of the present invention, the analysis module receives the optical path mode mark in the arbitration decision result, and when the mark indicates the short optical path output mode, the long optical path calculation task is interrupted; The pulse signal processing submodule of the analysis module receives the short optical path spectrum data in the gas spectrum data and extracts the absorption peak mutation characteristics; The pulse signal processing submodule generates a concentration versus time curve; The concentration and time curve is input into the spectrum morphology recognition submodule of the analysis module, and the spectrum shape features are identified and then output to the pulse signal analysis result.

[0011] Furthermore, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy of the present invention, the spectrum morphology recognition submodule extracts the peak width and symmetry characteristics of the concentration-time curve; Calling a preset morphological template library to match the features and generate a morphological consistency index; The morphological consistency index is written into the formation permeability classification code field in the pulse signal analysis result.

[0012] Furthermore, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy of the present invention, the output module receives a system clock signal and superimposes a timestamp on the concentration value in the pulse signal analysis result; Reading the optical path mode mark in the arbitration decision result and encoding it into a state value; Associating the drilling depth data input in real time by the logging system with the formation permeability classification code; Integrate the concentration value, state value and classification code after the superimposed time stamp to generate triple data; The triplet data is pushed to the mud logging system through the communication interface.

[0013] Furthermore, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy described in the present invention, the communication interface receives triplet data and an error retransmission mechanism, and uses industrial protocol encapsulation to generate data frames; The communication interface adds a check code during the encapsulation process; Push the data frame with the checksum added to the mud logging system; The error retransmission mechanism monitors the response signal returned by the logging system; When the response signal indicates that the verification fails, the most recently stored valid frame data is retransmitted; The valid frame data is extracted from a local buffer of the communication interface.

[0014] In a second aspect, the present invention provides a dual-mode hydrocarbon source gas detection method based on non-dispersive infrared spectroscopy, which is applied to the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy, comprising: Step 1: Collect dynamically released hydrocarbon gas through a gas permeation unit, generate dual-path independent transmission spectra using a non-dispersive infrared light source, and output gas spectrum data including a transmittance matrix; Step 2: arbitrating the gas spectrum data, dynamically selecting a short optical path or a long optical path output mode according to a confidence index, and generating an arbitration decision result including an optical path mode label; Step 3: receiving the gas spectrum data and the arbitration decision result, analyzing the pulse signal and identifying the spectrum morphological characteristics, and outputting the pulse signal analysis result including the concentration value and the formation permeability classification code; Step 4: fusing the concentration value in the pulse signal analysis result, the optical path mode mark in the arbitration decision result, and the formation permeability classification code, and outputting triplet data to the logging system. The triplet data includes depth data, concentration data, and morphology data. The gas spectrum data outputted from step 1 is passed to step 2 and step 3, the arbitration decision result outputted from step 2 is passed to step 3 and step 4, the pulse signal analysis result outputted from step 3 is passed to step 4, and step 4 pushes triplet data to capture transient gas release characteristics.

[0015] Beneficial effects of the present invention: The beneficial effects of the present invention are that the dual-optical path arbitration mechanism dynamically adapts to the gas release characteristics, the short optical path captures millisecond-level concentration pulse signals with high time domain resolution, and the arbitration module switches the detection mode in real time according to the characteristic absorption peak change rate, eliminating the time mismatch between the fixed sampling period and the transient release event; the resource scheduling algorithm of the analysis module interrupts non-critical computing tasks, concentrates on processing the spectral absorption peak mutation characteristics, generates millisecond-level concentration time curves and extracts peak width symmetry parameters, and converts them into formation permeability classification codes, avoiding the omission of weak abnormal characteristics by manual interpretation; the output module superimposes high-precision timestamps and associates drilling depth coordinates, fuses the optical path state values ​​to form depth concentration morphology triplet data, and is encapsulated by industrial protocols and transmitted through a communication link with a retransmission mechanism. The gas release characteristic data cross-validated in the time and space dimensions is solidified in real time to the logging system, blocking the risk of key geological signal loss caused by manual recording lag and subjective misjudgment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the present invention, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, for ordinary technicians in this field, other drawings can be obtained based on the drawings without paying any creative labor.

[0017] Figure 1 This is a system architecture diagram of a dual-mode hydrocarbon source gas detection method based on non-dispersive infrared spectroscopy provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0018] In order to make the purpose, present invention and advantages of the present invention clearer, the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and corresponding drawings. Obviously, the embodiments described are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. The present invention provided by each embodiment of the present invention is described in detail below in conjunction with the drawings. In order to better understand the purpose of the present invention, the present invention is further described below.

[0019] In a first aspect, the present invention provides a dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy, comprising: A data acquisition module is used to collect dynamically released hydrocarbon gas through a gas permeation unit, generate dual-path independent transmission spectra using a non-dispersive infrared light source, and output gas spectrum data including a transmittance matrix; an arbitration module, configured to arbitrate the gas spectrum data, dynamically select a short optical path or a long optical path output mode according to a confidence index, and generate an arbitration decision result including an optical path mode label; an analysis module, configured to receive the gas spectrum data and the arbitration decision result, analyze the pulse signal and identify the spectral morphological features, and output the pulse signal analysis result including the concentration value and the formation permeability classification code; an output module, configured to fuse the concentration value in the pulse signal analysis result, the optical path mode mark in the arbitration decision result, and the formation permeability classification code, and output triplet data to the logging system, wherein the triplet data includes depth data, concentration data, and morphology data; The gas spectrum data output by the data acquisition module is transmitted to the arbitration module and the analysis module, the arbitration decision result output by the arbitration module is transmitted to the analysis module and the output module, the pulse signal analysis result output by the analysis module is transmitted to the output module, and the output module pushes triplet data to capture transient gas release characteristics to solve the problem of missed judgment caused by the mismatch between the manual intervention detection cycle and the dynamic release signal.

[0020] The data acquisition module's gas permeation unit is equipped with a fluoropolymer semipermeable membrane. Based on the principle of molecular sieves, this membrane selectively isolates liquid components and solid cuttings from the drilling fluid while allowing small hydrocarbon gas molecules to diffuse and penetrate. Once hydrocarbon gas molecules enter the sealed detection chamber, a non-dispersive infrared light source generates a broad-spectrum infrared beam, which is then split by a beam splitter into two independently transmitted short and long optical paths. The short optical path utilizes a direct optical path design, allowing the beam to directly illuminate the detector. The long optical path is folded multiple times through a reflector array to form a folded optical path. Transmission spectral data is acquired separately from the two channels and then merged to generate gas spectral data in the form of a transmittance matrix.

[0021] After receiving gas spectral data, the arbitration module calculates the signal-to-noise ratio (SNR) of the characteristic absorption peak in the short optical path channel and the interference rejection ratio (ISR) of the long optical path channel. The SNR quantifies the spectral signal confidence of the methane characteristic band, while the ISR of the long optical path assesses the interference rejection capability of the water vapor interference band. These two confidence metrics are input into the arbitration rule engine. When the rate of change of the characteristic absorption peak exceeds a dynamic threshold, the short optical path output mode is activated. When the concentration of the environmental interfering component exceeds the limit, the long optical path mode is forced to switch. The final arbitration decision result is output, which carries the optical path selection flag.

[0022] The analysis module synchronously receives gas spectrum data and arbitration decision results. When the optical path mode flag indicates short-path mode, it interrupts the long-path data processing thread and allocates computing resources to the short-path channel. The pulse signal processing unit extracts the absorption peak mutation characteristics of the short-path spectrum and generates a dynamic curve of concentration change over time. This curve is input into the spectrum morphology recognition unit, which analyzes the peak width geometric characteristics and symmetry parameters to match the preset formation permeability type template. The generated morphology consistency index is written into the formation permeability classification code field, and the pulse signal analysis result, including the concentration value and classification code, is output.

[0023] The output module links the system timing unit with the logging system depth sensor. The system clock signal is a concentration value superimposed with a time stamp. The optical path pattern mark is encoded and converted into a state identifier. The drilling depth data is linked to the formation permeability classification code to form a depth morphology map. These three data sets are fused to generate a triplet data set, which is encapsulated using the industrial bus protocol and then cyclic redundancy check (CRC) is added. When the encapsulated data frame is pushed to the logging system via the communication interface, the error retransmission mechanism monitors the link layer response signal. If the check fails, the latest valid frame in the local cache is retransmitted.

[0024] Each module forms a closed-loop data processing chain: the gas permeation physical layer acquires the raw signal, the arbitration layer dynamically optimizes the detection path, the analysis layer identifies transient release characteristics, and the output layer integrates information in both temporal and spatial dimensions. Data streams are continuously transmitted from the spectral acquisition end to the communication output end. The spectral feature dimensions are cross-validated with the engineering parameter dimensions, eliminating the temporal mismatch between manual interpretation cycles and dynamic release events.

[0025] Specifically, the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy of the present invention comprises a gas permeation unit comprising a fluoropolymer semipermeable membrane, which isolates liquid and rock debris while allowing hydrocarbon gas molecules to penetrate into the detection cavity; The permeated hydrocarbon gas molecules are transmitted to the detection cavity, and a non-dispersive infrared light source irradiates the gas molecules in the detection cavity to generate gas spectrum data.

[0026] The fluoropolymer semipermeable membrane is constructed from polytetrafluoroethylene or perfluoroalkoxy resin, and its microporous structure enables selective permeability based on the kinetic diameter of gas molecules. Positioned between the drilling fluid flow path and the detection chamber, the membrane features surface pores with diameters ranging from 0.3 to 0.5 nanometers, effectively blocking liquid water molecules and rock debris larger than 1 micron. Hydrocarbon gas molecules, with molecular diameters of 0.38 nanometers for methane and 0.44 nanometers for ethane, penetrate the membrane structure through molecular diffusion, forming a gas-rich zone within the detection chamber.

[0027] The permeation process follows Fick's law of diffusion, with hydrocarbon gas molecules continuously migrating into the detection chamber driven by a concentration gradient. The detection chamber maintains a constant negative pressure, controlled by a microvacuum pump to maintain the internal pressure 0.1 to 0.3 atmospheres below the external drilling fluid pressure. This pressure differential accelerates the rate at which gas molecules penetrate the semipermeable membrane while preventing reverse permeation of the drilling fluid. As the concentration in the gas-rich zone increases, a non-dispersive infrared light source emits a broad-spectrum infrared beam vertically penetrating the detection chamber.

[0028] The non-dispersive infrared light source utilizes a silicon carbide ceramic-based blackbody radiator, operating at a temperature maintained between 600 and 800 Kelvin. The radiation beam enters the detection cavity through a calcium fluoride optical window and penetrates a gas-rich region with an optical path length of 15 to 30 mm. Hydrocarbon gas molecules absorb infrared energy of specific wavelengths, causing the transmitted light intensity to attenuate. The attenuation characteristic is related to the gas concentration in accordance with the Beer-Lambert law. This process generates the raw spectral signal that is input into the photoelectric conversion unit.

[0029] The output port of the detection cavity is connected to a dual-path beamsplitting system. The beamsplitter splits the attenuated infrared beam into independent transmission paths. The dual-channel optical signals are spatially separated and transmitted to a short-path detector and a long-path detector, respectively, to avoid measurement errors caused by optical crosstalk. The two detectors simultaneously collect transmission spectrum data, providing the basis for dual-mode detection in the subsequent arbitration module.

[0030] The gas permeation unit and optical detection unit form a tandem working chain: the semipermeable membrane separates and extracts substances, the detection chamber standardizes the gaseous medium, and the optical system captures molecular absorption characteristics. This design eliminates the obstruction of optical measurements caused by mud foam and the risk of optical damage caused by rock debris scratching, maintaining the continuity and stability of the spectral data acquisition process.

[0031] Specifically, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy described in the present invention, the dual-path beam splitter receives a non-dispersive infrared light source and divides the incident light into a short optical path channel beam and a long optical path channel beam; The short optical path channel light beam illuminates the first detector through a direct path to generate first spectral data; The long optical path channel light beam folds the light path through the reflector group and then illuminates the second detector to generate second spectral data; The first spectral data and the second spectral data are combined to form the gas spectral data, which is then transmitted to the arbitration module.

[0032] The beam splitter utilizes a cubic prism-structured optical beam splitter, with its incident surface coated with a broadband antireflection coating to reduce reflection losses. A divergent beam from a non-dispersive infrared light source is converted into parallel light by a collimating lens and then incident on the beam splitter's dichroic coating. This coating achieves a semi-transmissive, semi-reflective characteristic in the 3 to 5 micron wavelength range, splitting the incident beam into a transmitted short-path channel and a reflected long-path channel, with the two beams maintaining a 90-degree orthogonal propagation direction.

[0033] The short-path channel beam propagates along a straight path, with the beam divergence angle controlled within 0.2 degrees. An achromatic focusing lens is installed in the direct optical path to converge the parallel beam onto the photosensitive target surface of the first detector. The first detector utilizes a lead sulfide photoconductive sensor with a response time of less than 10 milliseconds. After the beam penetrates the gas sample within the 5mm effective optical path, the light intensity attenuation signal is converted into the first spectral data electrical signal via a transimpedance amplifier.

[0034] After reflection from a beam splitter, the long-path channel beam enters a folding system consisting of four sets of off-axis parabolic mirrors. The first reflector deflects the beam 90 degrees, and the subsequent three sets of mirrors extend the optical path length to 50 times the reference distance using a non-coplanar folding mechanism. The output beam from the final reflector is focused by a spherical field mirror and illuminates the mercury cadmium telluride (HgCdTe) photovoltaic sensitive area of ​​the secondary detector. During the folding process, the beam travels a distance of 150 mm, generating high-resolution secondary spectral data.

[0035] The dual-channel data synchronization acquisition unit includes a clock phase-locking circuit. The output signals of the first and second detectors are time-stamped using a synchronous sample-and-hold circuit. The two electrical signals are input into a differential analog-to-digital converter and combined to form a composite spectral dataset after eliminating common-mode noise. This dataset contains a dual-channel transmittance matrix whose data dimensions correspond to the characteristic absorption lines of the gas molecules.

[0036] The beam-splitting structure forms a dual-mode collaborative measurement system: the short optical path maintains high temporal resolution, rapidly capturing transient gas pulse changes; the long optical path provides high-sensitivity detection, accurately quantifying low-concentration gas components. The physical isolation of the two data paths avoids spectral aliasing errors associated with traditional time-sharing measurements, providing a foundation for differentiated feature analysis in the arbitration module.

[0037] Specifically, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy described in the present invention, the arbitration module calculates the short optical path signal-to-noise ratio as a partial confidence indicator, and the short optical path signal-to-noise ratio quantifies the signal reliability of the characteristic absorption peak in the gas spectral data; At the same time, the long optical path interference suppression rate is calculated as another confidence indicator. The long optical path interference suppression rate evaluates the anti-interference ability of the interference band in the gas spectrum data; The confidence index is input into the arbitration rule execution submodule, which selects the optical path mode according to the confidence index and outputs the arbitration decision result.

[0038] After the arbitration module receives dual-channel gas spectral data, the short-path data processing unit calculates the signal-to-noise ratio (SNR) of the characteristic absorption peak. This parameter is determined by comparing the amplitude variation of the absorption valley in the characteristic methane band with the baseline noise level, which originates from detector dark current and light source fluctuations. The SNR quantification coefficient reflects the ability of the current short-path channel to track transient gas concentration changes. A higher SNR value indicates a more reliable signal.

[0039] The long-path data processing unit simultaneously calculates the interference rejection coefficient, focusing on the background noise attenuation characteristics of the water vapor interference band. The anti-interference capability is assessed using a band-stop filtering algorithm to eliminate non-target gas absorption lines while preserving the integrity of hydrocarbon characteristic peaks. The interference rejection coefficient directly correlates to the measurement system's stability in aqueous drilling fluid environments; higher values ​​indicate better environmental adaptability.

[0040] The confidence indicator analysis engine processes dual-path parameters using a sliding time window. High-response mode is triggered when the short-path signal-to-noise ratio fluctuates above a dynamically preset threshold; environmental interference alarms are triggered when the long-path interference suppression rate falls below a critical value. These two indicators are fed into a rule-base matcher to achieve weighted decision-making, based on historical operating data analysis and formation fluid property models.

[0041] The arbitration rule execution submodule generates arbitration decision results, including a lightpath mode flag. When the short-path signal-to-noise ratio (SNR) consistently remains within the figure-of-merit range, the mode flag is set to a high-response state. When the interference suppression rate falls below a safety threshold, the flag switches to interference-rejection mode. The output decision results carry a timestamp and channel selection parameters, providing lightpath control instructions to downstream modules.

[0042] A dual-mode arbitration mechanism forms the core of adaptive detection: the signal-to-noise ratio ensures real-time pulse signal capture, while interference suppression maintains measurement accuracy in complex environments. The system dynamically switches optical path characteristics based on formation gas release characteristics, resolving mismatches between fixed detection modes and dynamic release processes. Decision results are synchronously transmitted to the analysis and output modules via the data bus.

[0043] Specifically, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy of the present invention, the arbitration rule execution submodule receives the confidence index and selects the short optical path output mode according to whether the characteristic absorption peak change rate in the confidence index exceeds a set threshold; When the environmental interference parameter exceeds the standard, the long optical path output mode is forced to be selected, and the component corresponding to the long optical path interference suppression rate of the environmental interference parameter exceeds the standard; The submodule outputs the arbitration decision result to the analysis module and the output module, and the light path selection mark is generated from the decision result.

[0044] After receiving the confidence indicator input, the arbitration rule execution submodule calculates the instantaneous slope of the methane characteristic band in real time using the characteristic absorption peak change rate analysis unit. This slope is calculated by taking the first-order derivative of the spectral data using a differential algorithm and reflects the rate of change of gas concentration. When the differential value exceeds the dynamically adjusted threshold for three consecutive sampling periods, the logic processor determines that the conditions for activating the short optical path mode have been met. The decision state machine sets the high response flag, indicating that the short optical path data channel is preferred.

[0045] The environmental interference monitoring unit concurrently monitors the long-path interference rejection ratio, focusing on the suppression level of water vapor interference components in the characteristic wavelength band. When the absorption intensity of water vapor in the 3.0-micron wavelength band exceeds a preset safety margin, the rejection coefficient falls below the critical level. The state converter triggers a forced switch command, overwriting the current optical path mode settings and locking the optical path selection parameters to the long-path interference rejection mode.

[0046] The decision result generation engine integrates the dual-path judgment signals and outputs a structured arbitration decision result. The result data structure consists of a timestamp, an optical path mode tag, and a confidence parameter snapshot. The optical path mode tag uses a binary encoding format to represent the channel selection status with minimal data. The timestamp is synchronized with the data acquisition module's acquisition clock to maintain system-wide timing consistency.

[0047] Decision results are synchronously transmitted to downstream modules via a parallel data bus. Data packets transmitted to the analysis module include a pointer to the original spectral index, maintaining the association between the spectral data and the decision parameters. Decision results transmitted to the output module are separated from the optical path selection tag, which is converted into a state identifier during the data integration phase. A data frame check mechanism is implemented during the transmission process to prevent transmission errors from causing inaccurate control instructions.

[0048] A dynamic decision-making mechanism forms the core of dual-mode collaborative control: monitoring characteristic absorption peak changes ensures timely pulse signal capture, while determining environmental interference thresholds maintains measurement reliability. An arbitration mechanism based on real-time operating conditions optimizes detection resource allocation, establishing a balance between transient response and interference resistance. The output of optical path mode markers provides a unified control benchmark for downstream processing, supporting the system's adaptive operation in complex formation conditions.

[0049] Specifically, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy of the present invention, the analysis module receives the optical path mode mark in the arbitration decision result, and when the mark indicates the short optical path output mode, the long optical path calculation task is interrupted; The pulse signal processing submodule of the analysis module receives the short optical path spectrum data in the gas spectrum data and extracts the absorption peak mutation characteristics; The pulse signal processing submodule generates a concentration versus time curve; The concentration and time curve is input into the spectrum morphology recognition submodule of the analysis module, and the spectrum shape features are identified and then output to the pulse signal analysis result.

[0050] When the optical path mode flag is read by the parsing module as short-path output mode, the computing resource scheduler immediately suspends long-path data processing tasks. This scheduler uses the interrupt controller to free up digital signal processor resources, reallocating floating-point units and memory bandwidth to the short-path data processing process. It also freezes write operations to the long-path data buffer to prevent invalid data from occupying the system bus, dynamically shifting computing resources toward critical channels.

[0051] The pulse signal processing submodule receives the redirected short-path spectral data stream. The feature extraction unit uses a sliding differential algorithm to track the trajectory of absorption peak changes. A second-order derivative transformation is performed on the spectral curve in the methane characteristic band, and zero-crossing detection is used to locate absorption peak mutation events. Each mutation point is associated with a timestamp and absorption depth parameter, forming a discrete feature point sequence that is output to the concentration reconstruction unit.

[0052] The concentration reconstruction unit converts the characteristic point sequence into concentration parameters based on the Beer-Lambert absorption law. The time dimension alignment module compensates for optical transmission delays and circuit response lags, generating a concentration data stream with millisecond-level time accuracy. This data stream is smoothed using a Kalman filter to output a dynamic curve of concentration over time. The curve data points are spaced at intervals sufficient to analyze transient release events.

[0053] The spectral morphology recognition submodule receives the concentration-time curve, and the characteristic geometry analyzer calculates the full-width at half-maximum (FWHM) parameter and symmetry index of the absorption peak. The FWHM parameter is used to obtain the peak broadening characteristics through Gaussian fitting, and the symmetry index is quantified using the left and right half-maximum area ratio method. These two parameters are input into the template matching engine and compared with pre-stored templates for high-permeability fractures, medium-permeability pores, and low-permeability dense formations.

[0054] The morphological feature recognition results are written into the pulse signal analysis result data structure. This structure consists of a concentration data array, a formation permeability classification code, and a feature confidence score. The formation permeability classification code uses a three-bit encoding scheme to represent the matching template type and its morphological consistency level. The final results are transmitted to the output module via a parallel bus, completing the dynamic feature analysis of the pulse release event.

[0055] Specifically, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy of the present invention, the spectrum morphology recognition submodule extracts the peak width and symmetry characteristics of the concentration-time curve; Calling a preset morphological template library to match the features and generate a morphological consistency index; The morphological consistency index is written into the formation permeability classification code field in the pulse signal analysis result.

[0056] The peak width feature extraction unit receives the concentration-time curve and calculates the gas absorption peak width using a full-width-at-half-maximum (FWHM) algorithm. This algorithm locates the absorption peak apex to the maximum concentration and defines the width boundary points where the concentration drops by 50% on either side of the peak. The peak width represents the diffusion rate of the gas release process. Simultaneously, the symmetry calculation module analyzes the geometric characteristics of the peak profile. The ratio of the distance from the left boundary to the peak apex to the distance from the right boundary to the peak apex is used to quantify the peak symmetry index, reflecting the uniformity of the formation's permeability structure.

[0057] The feature parameter set is input into the template matching engine, which then uses a pre-stored library of formation permeability morphology templates for similarity comparison. The template library contains three types of standard patterns: high-permeability fractured patterns, medium-permeability porous patterns, and low-permeability dense patterns. Each template type stores the peak width benchmark values ​​and symmetry benchmark ranges for typical concentration-time curves. Similarity calculations use the Euclidean distance algorithm, mapping the measured peak widths and symmetry into a multidimensional feature space and measuring their deviation from the standard templates.

[0058] The matching result generation module outputs a morphological consistency index, which expresses the degree of agreement between the measured features and the target template as a percentage. The index is calculated by combining the weighted results of peak width matching and symmetry deviation, with weighting coefficients preset based on empirical geological exploration data. When the measured parameters fall within both the peak width and symmetry tolerance bands of the target template, the index automatically increases to the optimal range.

[0059] The data write controller loads the morphological consistency index into the structured dataset of the pulse signal analysis results and locks the entry into the formation permeability classification code field. The classification code uses a three-bit binary encoding format, with the high-order bit identifying the template type and the low-order bit carrying the index classification information. The write operation is synchronized with the original concentration data timestamp to maintain the temporal and spatial consistency of the data record.

[0060] A template-driven analysis mechanism maps spectral morphology to geological attributes: peak width reflects the migration capacity of formation fluids, while symmetry indicates the heterogeneity of reservoir pore structure. The consistency index, a quantitative evaluation metric embedded in the classification code structure, provides the logging system with programmable and analyzable permeability parameters, enabling rapid identification of reservoir properties during drilling.

[0061] Specifically, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy of the present invention, the output module receives a system clock signal and superimposes a timestamp on the concentration value in the pulse signal analysis result; Reading the optical path mode mark in the arbitration decision result and encoding it into a state value; Associating the drilling depth data input in real time by the logging system with the formation permeability classification code; Integrate the concentration value, state value and classification code after the superimposed time stamp to generate triple data; The triplet data is pushed to the mud logging system through the communication interface.

[0062] The system clock signal is input and output to the module via a precision timing circuit. This signal source is synchronized with the Coordinated Universal Time system. A timestamp superposition processor reads the concentration data stream from the pulse signal analysis results and uses a hardware-level time-stamping unit to add a microsecond-level time stamp to each concentration sampling point. This stamping process adheres to the IEEE 1588 precision time protocol. The time stamp is embedded in the extended field of the concentration data frame, forming an enhanced data packet with complete time domain characteristics.

[0063] The optical path mode signature decoder extracts the binary-coded signal from the arbitration decision. The signature conversion logic performs state mapping according to a predefined encoding table, encoding short optical path modes as high-response state identifiers and long optical path modes as interference-resistant state identifiers. This conversion process maintains the integrity of the encoding metadata, ensuring that the output state value maintains a strict correspondence with the original signature.

[0064] The drilling depth correlation unit connects to the logging system's data bus and acquires drilling depth pulse signals generated by the rotary encoder in real time. The depth data calibration module eliminates drill pipe compression errors and measurement hysteresis, generating an absolute coordinate value for the current well depth. This coordinate value is indexed and associated with the formation permeability classification code within the relational database, binding the depth data to formation characteristic parameters through a foreign key constraint mechanism.

[0065] The data fusion engine performs three-way information integration. Time-stamped concentration packets are loaded into the triplet concentration data field, optical path status identifiers are written into the status value field, and depth-indexed formation permeability classification codes are loaded into the morphology data field. The fusion process follows the packet serialization protocol, generating structured triplet data blocks with a frame synchronization sequence and length checksum in the block header.

[0066] The communication interface controller receives triplet data blocks and encapsulates the application layer data using the industrial real-time Ethernet protocol. The encapsulation process adds a transmission control header and data link layer address, and pushes the data to the remote terminal of the mud logging system via the physical layer signal driver. The push mechanism uses both periodic and event-triggered modes, prioritizing transmission of abnormal status data while maintaining the basic transmission rate.

[0067] A multidimensional data fusion mechanism builds a feature correlation system: time stamping enables the temporal location of transient gas events, depth correlation establishes a vertical distribution map of formation characteristics, and state identification feedback monitors system operating conditions. The triplet data structure provides the analytical foundation for temporal and spatial correlations in the logging system, supporting the dynamic geological interpretation of gas release events during drilling.

[0068] Specifically, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy described in the present invention, the communication interface receives triplet data and an error retransmission mechanism, and uses industrial protocol encapsulation to generate data frames; The communication interface adds a check code during the encapsulation process; Push the data frame with the checksum added to the mud logging system; The error retransmission mechanism monitors the response signal returned by the logging system; When the response signal indicates that the verification fails, the most recently stored valid frame data is retransmitted; The valid frame data is extracted from a local buffer of the communication interface.

[0069] The data encapsulation unit of the communication interface receives the triplet data stream generated by the output module and uses the real-time Industrial Ethernet protocol as the application layer transmission standard. The encapsulation process builds a seven-layer protocol stack structure, adding the destination MAC address and source device identifier at the data link layer, allocating the IP datagram header at the network layer, and implementing the TCP retransmission control mechanism at the transport layer. The application layer payload consists of triplet data blocks, and the entire data frame structure conforms to the ISO / IEC standardized framework.

[0070] The frame check sequence generator performs a cyclic redundancy check (CRC) calculation at the end of the encapsulation process. This calculation generates a 32-bit checksum based on the CRC-32 polynomial, which is appended to the frame check sequence field at the end of the data frame. The checksum covers the entire range from the start of the frame to the end of the application layer data, providing bit error detection during transmission. Data frames with the checksum added are temporarily stored in the transmit buffer.

[0071] The data frame push engine extracts complete frames from the buffer queue and converts them into Manchester-encoded electrical signals via the physical layer differential signal driver. These signals are then transmitted to the receiving end of the mud logging system via twisted-pair or optical fiber. The push sequence controller utilizes both fixed-cycle polling and interrupt-triggered modes, prioritizing the transmission of abnormally marked data frames while maintaining the base transmission rate.

[0072] The response monitoring unit of the error retransmission mechanism continuously monitors link layer control signals. The standard response protocol generated by the receiving end of the logging system includes a frame sequence number confirmation and a check status bit. The status analyzer compares the transmitted frame sequence number with the confirmation number in the response frame. If the check status bit indicates a failure or if no response is received three times in a row, a data retransmission request signal is triggered.

[0073] After responding to a retransmission request, the retransmission executor retrieves the most recently valid frame data from the communication interface's local ring buffer. This buffer stores original copies of transmitted frames and maintains a fixed capacity using a first-in, first-out replacement strategy. Retransmitted frames are marked with a special retransmission flag and inserted into the head of the transmit queue, taking precedence over regular data frames. If a failure response is still received after retransmission, the process escalates to an exception handling process and updates the link quality assessment report.

[0074] Data integrity maintenance mechanisms establish a transmission reliability assurance system: standardized protocol encapsulation maintains compatibility across heterogeneous systems, cyclic redundancy checks provide bit-level error detection, and response monitoring and retransmission control respond to fluctuations in link quality. A local cache mechanism provides temporary storage for critical data, preventing geological information loss caused by transient failures and enabling the logging system to continuously acquire highly reliable formation gas release signatures.

[0075] Second, see Figure 1 The dual-mode hydrocarbon source gas detection method based on non-dispersive infrared spectroscopy provided by the present invention is applied to the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy, comprising: Step 1: Collect dynamically released hydrocarbon gas through a gas permeation unit, generate dual-path independent transmission spectra using a non-dispersive infrared light source, and output gas spectrum data including a transmittance matrix; Step 2: arbitrating the gas spectrum data, dynamically selecting a short optical path or a long optical path output mode according to a confidence index, and generating an arbitration decision result including an optical path mode label; Step 3: receiving the gas spectrum data and the arbitration decision result, analyzing the pulse signal and identifying the spectrum morphological characteristics, and outputting the pulse signal analysis result including the concentration value and the formation permeability classification code; Step 4: fusing the concentration value in the pulse signal analysis result, the optical path mode mark in the arbitration decision result, and the formation permeability classification code, and outputting triplet data to the logging system. The triplet data includes depth data, concentration data, and morphology data. The gas spectrum data outputted from step 1 is passed to step 2 and step 3, the arbitration decision result outputted from step 2 is passed to step 3 and step 4, the pulse signal analysis result outputted from step 3 is passed to step 4, and step 4 pushes triplet data to capture transient gas release characteristics.

[0076] The dual optical paths of the present invention generate independent short and long optical path channels through a beam splitter, maintaining high temporal resolution in the short optical path. The arbitration module calculates the dual confidence indicators of the short optical path characteristic absorption peak change rate and the long optical path interference suppression rate in real time. When the characteristic absorption peak change exceeds a dynamic threshold, the short optical path mode is immediately activated. The optical path mode flag triggers the analysis module to interrupt the long optical path calculation task, concentrating computing power on processing the millisecond-level pulse signals of the short optical path spectrum, thus avoiding the omission of transient signals caused by manually set fixed sampling periods.

[0077] The pulse signal processing submodule of the analysis module extracts the trajectory of abrupt changes in short-path spectral absorption peaks and generates millisecond-scale concentration-time curves. The spectral morphology recognition submodule analyzes the peak width and symmetry of the curves, matches them to pre-set templates for high-permeability fractures, medium-permeability pores, and low-permeability dense formations, generates a morphology consistency index, and stores it in a formation permeability classification code. This process converts transient gas release characteristics into quantifiable formation parameters, preventing manual interpretation from overlooking weak anomalous signals.

[0078] The output module superimposes microsecond-level timestamps on concentration values, simultaneously linking the real-time drilling depth and formation permeability classification codes from the logging system. The fused depth-concentration-morphology triplet data is encapsulated using industrial protocols and pushed to the logging system via an error-retransmission mechanism. The time dimension locks in the pulse occurrence moment, the depth dimension correlates and locates the released horizon, and the morphology classification codes translate into geological significance. These three dimensions of data collaboratively construct an irreversible record chain, eliminating the loss of critical information due to manual recording delays and misjudgments.

Claims

1. A dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy, characterized in that: include: A data acquisition module is used to collect dynamically released hydrocarbon gas through a gas permeation unit, generate dual-path independent transmission spectra using a non-dispersive infrared light source, and output gas spectrum data including a transmittance matrix; an arbitration module, configured to arbitrate the gas spectrum data, dynamically select a short optical path or a long optical path output mode according to a confidence index, and generate an arbitration decision result including an optical path mode label; an analysis module, configured to receive the gas spectrum data and the arbitration decision result, analyze the pulse signal and identify the spectral morphological features, and output the pulse signal analysis result including the concentration value and the formation permeability classification code; an output module, configured to fuse the concentration value in the pulse signal analysis result, the optical path mode mark in the arbitration decision result, and the formation permeability classification code, and output triplet data to the logging system, wherein the triplet data includes depth data, concentration data, and morphology data; The gas spectrum data output by the data acquisition module is transmitted to the arbitration module and the analysis module, the arbitration decision result output by the arbitration module is transmitted to the analysis module and the output module, the pulse signal analysis result output by the analysis module is transmitted to the output module, and the output module pushes triplet data to capture transient gas release characteristics.

2. The dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy according to claim 1 is characterized in that: The gas permeation unit includes a fluoropolymer semipermeable membrane, which isolates liquid and rock debris while allowing hydrocarbon gas molecules to penetrate into the detection cavity; The permeated hydrocarbon gas molecules are transmitted to the detection cavity, and a non-dispersive infrared light source irradiates the gas molecules in the detection cavity to generate gas spectrum data.

3. The dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy according to claim 2 is characterized in that: The dual-path beam splitter receives a non-dispersive infrared light source and splits the incident light into a short optical path channel light beam and a long optical path channel light beam; The short optical path channel light beam illuminates the first detector through a direct path to generate first spectral data; The long optical path channel light beam passes through a reflector group to fold the light path and then illuminates a second detector to generate second spectral data; The first spectral data and the second spectral data are combined to form the gas spectral data, which is then transmitted to the arbitration module.

4. The dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy according to claim 3 is characterized in that: The arbitration module calculates a short optical path signal-to-noise ratio as a partial confidence indicator, and the short optical path signal-to-noise ratio quantifies the signal reliability of a characteristic absorption peak in the gas spectrum data; At the same time, the long optical path interference suppression rate is calculated as another confidence indicator. The long optical path interference suppression rate evaluates the anti-interference ability of the interference band in the gas spectrum data; The confidence index is input into the arbitration rule execution submodule, which selects the optical path mode according to the confidence index and outputs the arbitration decision result.

5. The dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy according to claim 4 is characterized in that: The arbitration rule execution submodule receives the confidence index and selects the short optical path output mode according to whether the characteristic absorption peak change rate in the confidence index exceeds a set threshold; When the environmental interference parameter exceeds the standard, the long optical path output mode is forced to be selected, and the component corresponding to the long optical path interference suppression rate of the environmental interference parameter exceeds the standard; The submodule outputs the arbitration decision result to the analysis module and the output module, and the light path selection mark is generated from the decision result.

6. The dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy according to claim 5, characterized in that: The analysis module receives the optical path mode mark in the arbitration decision result, and interrupts the long optical path calculation task when the mark indicates the short optical path output mode; The pulse signal processing submodule of the analysis module receives the short optical path spectrum data in the gas spectrum data and extracts the absorption peak mutation characteristics; The pulse signal processing submodule generates a concentration versus time curve; The concentration and time curve is input into the spectrum morphology recognition submodule of the analysis module, and the spectrum shape features are identified and then output to the pulse signal analysis result.

7. The dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy according to claim 6, characterized in that: The spectrum morphology recognition submodule extracts the peak width and symmetry characteristics of the concentration-time curve; Calling a preset morphological template library to match the features and generate a morphological consistency index; The morphological consistency index is written into the formation permeability classification code field in the pulse signal analysis result.

8. The dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy according to claim 7, characterized in that: The output module receives the system clock signal and adds a timestamp to the concentration value in the pulse signal analysis result; Reading the optical path mode mark in the arbitration decision result and encoding it into a state value; Associating the drilling depth data input in real time by the logging system with the formation permeability classification code; Integrate the concentration value, state value and classification code after the superimposed time stamp to generate triple data; The triplet data is pushed to the mud logging system through the communication interface.

9. The dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy according to claim 8, characterized in that: The communication interface receives triplet data and an error retransmission mechanism, and uses industrial protocol encapsulation to generate data frames; The communication interface adds a check code during the encapsulation process; Push the data frame with the checksum added to the mud logging system; The error retransmission mechanism monitors the response signal returned by the logging system; When the response signal indicates that the verification fails, the most recently stored valid frame data is retransmitted; The valid frame data is extracted from a local buffer of the communication interface.

10. A dual-mode hydrocarbon source gas detection method based on non-dispersive infrared spectroscopy, applied to a dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy as claimed in any one of claims 1 to 9, characterized in that: include: Step 1: Collect dynamically released hydrocarbon gas through a gas permeation unit, generate dual-path independent transmission spectra using a non-dispersive infrared light source, and output gas spectrum data including a transmittance matrix; Step 2: arbitrating the gas spectrum data, dynamically selecting a short optical path or a long optical path output mode according to a confidence index, and generating an arbitration decision result including an optical path mode label; Step 3: receiving the gas spectrum data and the arbitration decision result, analyzing the pulse signal and identifying the spectrum morphological characteristics, and outputting the pulse signal analysis result including the concentration value and the formation permeability classification code; Step 4: fusing the concentration value in the pulse signal analysis result, the optical path mode mark in the arbitration decision result, and the formation permeability classification code, and outputting triplet data to the logging system. The triplet data includes depth data, concentration data, and morphology data. The gas spectrum data outputted from step 1 is passed to step 2 and step 3, the arbitration decision result outputted from step 2 is passed to step 3 and step 4, the pulse signal analysis result outputted from step 3 is passed to step 4, and step 4 pushes triplet data to capture transient gas release characteristics.

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